How to use the espresso yield calculator
- Enter the dose of ground coffee and the weight of the drink in grams.
- Optionally enter the TDS of the drink as a percent, from your own refractometer, to get the extraction yield.
- Optionally enter the brew time in seconds to get the flow in grams per second.
- Read the brew ratio, the extraction yield and the flow.
Formula
Brew ratio = drink weight / dose, written 1:ratio
Extraction yield (%) = drink weight x TDS (%) / dose
Flow (g/s) = drink weight / brew time in seconds
These are the standard definitions of the brew ratio and extraction yield. The tool measures and does not judge taste.
18 g in, 36 g out, 9% TDS
The brew ratio is 36 / 18 = 2, written 1:2. The extraction yield is 36 x 9% / 18 = 18%, because the drink holds 36 x 0.09 = 3.24 g of dissolved coffee out of the 18 g dose.
Pull 40 g from the same 18 g at 8.5% TDS and the ratio is 1:2.22 and the extraction yield is 40 x 8.5 / 18 = 18.89%. A 36 g drink in 28 seconds flows at 1.29 grams per second.
What the numbers measure
The brew ratio compares the weight of the drink with the weight of the dry coffee. Extraction yield is the share of the dose that ended up dissolved in the cup. It needs a TDS reading, which is the percent of dissolved solids in the drink, measured with a refractometer.
Without a reading the tool shows only the ratio and flow. It does not guess the TDS from the ratio, since two drinks with the same ratio can have different readings.
Using the figures
Many people keep a note of dose, ratio, time and yield for each coffee and change one thing at a time. Which numbers you prefer is up to your own taste, and this tool does not claim any figure is better. To scale a recipe for brewed coffee, use the coffee ratio calculator, and to switch between grams and ounces use the unit converter.
If you are pricing drinks, add the cost of the dose to your other costs with the recipe cost calculator.
Assumptions and limits
- The drink weight is the weight of the liquid in the cup.
- The TDS reading is entered as a percent and comes from your own refractometer.
- Brew ratio uses weights, not volumes.
- Taste and quality are not judged by this tool.
Frequently asked questions
What is an espresso brew ratio?
It is the weight of the drink divided by the weight of the dry coffee. 36 g from an 18 g dose is a ratio of 1:2.
How is extraction yield calculated?
Multiply the drink weight by the TDS percent and divide by the dose. 36 g at 9% from 18 g gives 18%.
Do I need a refractometer?
Only for extraction yield. The brew ratio and flow need just a scale and a timer.
Is a higher extraction yield better?
The tool does not say. It reports what you measured, and which number tastes best is for you to decide.